A deadly disease called stony coral tissue loss disease is causing significant damage to susceptible species of coral in the Caribbean, as outlined in a study published in Science Advances. This disease, first observed off the coast of Miami in 2014, has spread rapidly throughout the region, affecting coral populations in 18 countries and territories. The exact cause of the disease is unknown, but it is believed to be a waterborne pathogen that rapidly deteriorates coral colonies, leaving no living tissue behind. The loss of susceptible corals is expected to have long-lasting consequences on the region’s ecosystem balance and marine biodiversity.
Researchers conducted a study analyzing data from the U.S. Virgin Islands, Florida, Puerto Rico, and other western Atlantic territories to assess the impact of stony coral tissue loss disease on fish and benthic reef communities. They found that not only does the disease reduce susceptible coral populations, but it also diminishes crustose coralline algae, which is essential for reef structure. As a result, fast-growing, weedy species such as macroalgae, cyanobacteria, and fire coral thrive in the absence of competition, creating a seaweed-dominated environment that lacks the hard structures necessary for biodiversity.
The study also revealed that the disease’s effects on fish populations vary, with some associations being positive. Coral rugosity, or roughness, was found to influence fish behavior more than whether the coral was alive or dead. Senior scientist Kevin Lafferty noted that while some ecosystems can be affected by infectious diseases, stony coral tissue loss disease has profound and complex impacts, with some species benefiting from the changes caused by the disease. The research team included experts from the University of Florida and the U.S. Geological Survey, and their work was funded by federal agencies.
International agencies, marine biologists, and conservationists across the Caribbean are actively responding to the crisis caused by stony coral tissue loss disease. Efforts are underway to understand the disease’s mechanisms and develop potential treatments to mitigate its effects on coral reefs. Probiotics have shown promise in slowing down or halting active lesions on affected corals. While the disease has not spread beyond the western Atlantic and Caribbean so far, the critical role of coral reefs as biodiversity hotspots and crucial habitats for marine species underscores the importance of preserving and protecting these ecosystems for coastal communities dependent on fishing and tourism.
Lead author Sara Swaminathan emphasized the importance of preserving coral reefs, stating that the loss of these natural habitats threatens the livelihoods of coastal communities and the ecosystems that depend on them. Reefs provide essential functions such as food, shelter, and breeding grounds for marine species, as well as protection for coastlines. The study underscores the urgent need to address the impacts of stony coral tissue loss disease and implement strategies to conserve coral reefs and the invaluable ecosystems they support.
